Product code

I re-installed my computer and when I want to give in my serial code I get the message that that key is already been taken by another user.
What can I do?

Welcome to the forum.

First, it would be helpful to know which version of Cubase you’re using. If you’re using any version of Cubase 12, you can just sign-in to the Steinberg Activation Manager.

It is the Cubase LE.
That is what I got for buyng a mike from Rode.

Please follow the step-by-step reactivation guide from this page:

If your license doesn’t show up in your MySteinberg/eLicenser-based products list, try registering the code that came with your microphone. If that doesn’t work, please contact Steinberg Support.